The present invention is related to an improved printing head structure of large-size drafting machine. The cost for the outputting device of the drafting machine is reduced so that the printing cost is lowered and a real remote visual effect can be achieved.
Various kinds of computerized printers are commercially available nowadays. It is known that a personal color ink-injecting printer is quite cheap and has high resolution. When co-used with a relevant image software, the printer can print a picture with high picture quality. However, this is limited to small-size print material. With respect to ink-injecting drafting machine for large-size picture, the requirement for high resolution and pixel leads to high technique and high price In addition, not all the large-size printing materials necessitate high picture quality. For example, the canvas-made commercial signs are mostly hung high above. Therefore, even if the printed picture has relatively coarse particles, the message presented thereby will make no difference to the sight of a common person. Therefore, in the case that such picture is printed with the existent high quality ink-injecting printer, the cost will be relatively high and the competitive ability on the market will be reduced.
It is therefore a primary object of the present invention to provide an improved printing head structure of large-size drafting machine. The cost for the outputting device of the drafting machine is reasonable and the printing cost is lowered, while a real remote visual effect can be still achieved.
It is a further object of the present invention to provide the above improved printing head structure of large-size drafting machine, in which the printing head can be accurately ascended/descended and located.
It is still a further object of the present invention to provide the above improved printing head structure of large-size drafting machine, in which the color cartridge can be easily received and rolled.
It is still a further object of the present invention to provide the above improved printing head structure of large-size drafting machine, in which a torque limiter is used to protect the color belt from being torn apart.
According to the above objects, the printing head structure of large-size drafting machine of the present invention includes a printing box movably retained on rails. The printing box has a receptacle in which a reel-type color cartridge is positioned. The box body is formed with a window at a printing position. A printing head is disposed in the box body. Two sides of the printing head are equipped with linear bearings. A shaft fitted in a spring is fitted in and supported by the bearing. Multiple electric heaters as printing points and heat-radiators are disposed under the printing head. A vertically movable cam driving mechanism is disposed above the printing head. According to received drafting signals, the color belts are rolled for selecting points and heating the points so as to print a picture.
The present invention can be best understood through the following description and accompanying drawings wherein: